Bio-inspired fabrication of asymmetric wettability Janus porous membrane for secure F-oil infused F-free-membrane filtration

Porous membranes, which consist of air-filled or liquid-filled pores, provide a gating strategy for tunable multiphase selectivity separation, and exhibit tremendous application potential in fields involving intelligent liquid management. Herein, we report the fabrication of a novel asymmetric wettability Janus porous membrane (JPM) based on bio-inspired models that integrate the air-gate floating mechanism and adhesive proteins secreted by mussels to attach to material-independent surfaces. The JPM fabricated through this novel and straightforward methodology has distinct hydrophobic-hydrophilic properties and interfacial compatibility. These features were engineered for F-oil (lubricant oil, Dupont Krytox 105) infused F-free JPM membrane filtration. The hydrophilic layer infused with high-surface-energy water acts as a perfect barrier (liquid gating) preventing invasion of the low-surface-energy F-oil which was infused in the hydrophobic surface, protecting the F-oil in the JPM. This is the first report regarding F-oil infused membrane filtration using the F-free-membrane, which can overcome the limitations of F-substrates for F-oil infused filtration.